An organic electro luminescence (EL) element is a current-driven type self-luminous element, therefore it has advantages that low power consumption, high viewing angle, high contrast ratio, and the like are obtained, as well as there is no need for a backlight, and it is considered to facilitate the ongoing development of flat panel displays.
An organic EL display apparatus using the above-described organic EL element forms a plurality of pixels by using sub-pixels of respective colors of red (R), green (G) and blue (B). Thereby, a variety of color images are displayed thereon. These sub-pixels of RGB may be arranged in various forms, however, as illustrated in FIG. 1, are generally arranged in a stripe type (a so-called RGB vertical stripe type) in which sub-pixels of the same color are equally arranged. By controlling the brightness between the sub-pixels of the three colors, it is possible to display all colors. Commonly, three sub-pixels of R, G and B adjacent to each other are treated as one rectangular pixel as a whole, and these pixels are disposed in a square shape, thereby achieving a dot matrix display. In the dot matrix type display apparatus, image data to be displayed are an n×m matrix arrangement, and by associating the image data with the pixels one to one, it is possible to display a correct image.
In addition, the organic EL display apparatus has a color filter type that produces three colors of R, G and B by a color filter based on a white organic EL element, and a side-by-side selective deposition type that selectively deposits organic EL materials of three colors of R, G and B with individually different colors. The color filter type has a drawback in that the utilization rate of light is reduced because the color filter absorbs light, and power consumption increases. Whereas, the side-by-side selective deposition type is an easy means to provide a wide color gamut due to high color purity, and has no color filter, therefore the utilization rate of light is increased. For these reasons, the side-by-side selective deposition type has been widely used.